Electronic book



FIG. 1 is a perspective view of an electronic book showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines shown in the drawings represent portions of the electronic book which form no part of the claimed design. 

The ornamental design for an electronic book, as shown and described. 